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Biomedical subjects

K Miyake

Publications and source records attributed to K Miyake.

At least 343 records · Page 19Linked to original sources
PubMed1993

Multivariate evaluation of prognostic determinants for renal cell carcinoma.

To clarify the relative importance of clinicopathological factors affecting survival in patients with renal cell carcinoma, univariate and multivariate analyses by Cox's proportional hazards model were performed for 121 patients undergoing nephrectomy between 1980 and 1991. The 5-year survival rate was 67% for all 121 patients. Univariate analysis revealed that distant metastasis, local invasion, venous involvement, infiltration pattern, grade, lymph node metastasis, sex, and tumor size were significantly associated with patient survival. Multivariate analysis using a method of stepwise selection revealed that presence or absence of distant metastasis is the most significant determinant (p < 0.0001) for survival, followed by venous involvement (p < 0.001), treatment period (p < 0.02) and local invasion (p < 0.02), in this order. A four-factor model of the above determinants yielded adjusted hazard ratios of 5.3 for distant metastasis (positive vs. negative), 3.7 for venous involvement (pV1a-pV2 vs. pV0), 3.9 for treatment period (1980-1984 vs. 1985-1991), and 3.1 for local invasion (pT3-pT4 vs. pT1-pT2). The present study revealed recent improvements in the patient survival and justified the clinical application of Robson's staging system implying local invasion, venous thrombus formation and distant metastasis as prognostic determinants.

Adult↗
PubMed1993

Metastasis of renal cell carcinoma to the contralateral renal pelvis.

Extremely rarely renal cell carcinoma metastasizes to the contralateral renal pelvis or ureter. The present report concerns a case where a metastatic tumor could be successfully removed from the left renal pelvis 3 years after right nephrectomy for the primary tumor. A review of the literature revealed this to be only the fourth such case documented.

Carcinoma, Renal Cell↗
PubMed1993

S100a0 protein as a marker for tissue damage related to extracorporeal shock wave lithotripsy.

We assayed serum and urine S100a0 protein levels in patients with renal stones (n = 21) or ureteral stones (n = 18), before and after extracorporeal shock wave lithotripsy (ESWL) to evaluate tissue injury. Serum S100a0 protein levels increased significantly immediately after, and at 2 and 24 h after ESWL in patients with renal stones, and at 2 and 24 h after ESWL in patients with ureteral stones. Significant increases in urine S100a0 protein levels were observed immediately and 2 h after ESWL in both groups of patients. The patients receiving a higher number of shock waves had a more pronounced increase in serum S100a0 protein especially in the case of more than 3,500 shock waves. Because S100a0 protein exists at relatively high concentrations in the proximal renal tubules and skeletal muscles, serum and urine S100a0 protein levels appear to be useful markers of tissue injury, including damage in the kidney and skeletal muscles, in the early post-ESWL phase.

Adult↗
PubMed1993

Sustained decrease in brain regional blood flow after microsphere embolism in rats.

BACKGROUND AND PURPOSE: An experimental model that induces sustained ischemia and infarction may provide useful information relevant to prevention of the development of ischemic brain disease. The purpose of the present study was to elucidate the pathophysiological consequences of cerebral blood flow under sustained cerebral ischemia or oligemia and infarction in rats after microsphere embolism. METHODS: We injected 900 microspheres (48 microns in diameter) into the right internal carotid artery of 146 rats and determined the time course of changes in blood flow of the cerebral cortex, striatum, and hippocampus of both hemispheres by the hydrogen clearance method for a period of 28 days after the operation. Infarct area was determined by triphenyltetrazolium chloride staining and hematoxylin and eosin staining methods. RESULTS: Cortical and striatal blood flow of the right hemisphere of microsphere-injected rats was significantly decreased after the embolism, and this was sustained throughout the experiment. Hippocampal blood flow of the microsphere-injected hemisphere was also decreased on days 1 and 3 but tended to return toward control levels thereafter. In the left hemisphere, reduction in regional blood flow was detected in the cortex and hippocampus on day 1 and the striatum on day 3. A triphenyltetrazolium chloride-unstained area had developed by day 3 after the embolism. The extent of the area was similar to that on days 7 and 28. Microscopic examination revealed degenerative areas scattered mainly in the parietotemporal cortex, corpus callosum, hippocampus, thalamus, and lenticular nucleus of the embolized hemisphere, demonstrating the induction of widespread necrosis after embolism. CONCLUSIONS: Microsphere embolism resulted in a sustained decrease in regional blood flow and production of cerebral infarction in the brain regions of the microsphere-injected hemisphere.

Animals↗
PubMed1993

Pharmacokinetic interaction of zonisamide in rats. Effect of zonisamide on other antiepileptics.

The effects of zonisamide (ZNS) on the pharmacokinetics of phenobarbital (PB), valproic acid (VPA), carbamazepine (CBZ) and phenytoin (PHT) were investigated in rats. Additionally, the influence of ZNS on the serum protein binding, erythrocyte distribution and metabolism of these antiepileptics was studied in vitro. The t 1/2 and AUC values of PB were significantly increased by ZNS coadministration, and a significant decrease in the Vd/F value of PHT was observed after multiple dosing of ZNS. By contrast, ZNS showed no significant effect on VPA and CBZ kinetics. No significant effect of ZNS was observed in the serum protein binding, erythrocyte distribution or metabolism of other antiepileptics. These results suggest that ZNS has little effect on the pharmacokinetic behaviors of other antiepileptic drugs.

Animals↗
PubMed1993

Sustained changes in acetylcholine and amino acid contents of brain regions following microsphere embolism in rats.

The present study was undertaken to explore changes in neurotransmitters and neuromodulators of brain regions impaired by microsphere embolism-induced, sustained ischemia. Nine hundred microspheres (48 microns) were injected into the right internal carotid artery of rats, and the time course of changes in the triphenyltetrazolium chloride (TTC)-stained areas of their brain slices and acetylcholine and amino acid contents in the cerebral cortex, striatum and hippocampus of both hemispheres were determined. The TTC-unstained area, a measure of infarction, was developed in the right hemisphere by the 3rd day after the embolism, which was similar to that on the 28th day. A marked decline in acetylcholine content of these three regions of the right hemisphere was detected throughout the experiment (28 days). The glutamate, aspartate, GABA, and taurine levels were markedly decreased following microsphere-embolism. Most of these decreases were significantly attenuated during the first 5 days following the embolism, and they then partially recovered with time after the operation. Minor metabolic changes were observed in the left hemisphere. The results suggest that microsphere-embolism induces cerebral infarction and/or sustained damage to acetylcholine and neurotransmitter amino acid synthesis and/or catabolism of the brain regions. This model may provide information concerning the pathophysiological alterations in long-term cerebral ischemia and infarction.

Acetylcholine↗
PubMed1993

In vivo profile of myocardial energy metabolism of pressure-overloaded rat.

Cardiac energy metabolism of pressure-overloaded rat hearts was examined under in vivo and in vitro conditions. Two, 4 and 6 weeks after constriction of the abdominal artery, the hemodynamic and metabolic profiles of hearts in vivo and of perfused hearts were determined. Significant increases in left ventricular weight/body weight (30 to 45% increase relative to the sham group), systolic and diastolic blood pressure (22 to 33% increase) and pressure-rate product (31 to 33% increase) were observed 2, 4 and 6 weeks after the operation, and a slight but significant decrease in heart rate was observed at 2 weeks after the operation. Tissue hydroxyproline content increased (17 to 93%) with time after pressure-overload. These findings are indicators of pressure-overloaded cardiac hypertrophy. The total high-energy phosphates of the in vivo rat myocardium under artificial respiration were lower than those of sham-operated rat myocardium 2 (23%) and 4 weeks (21%), but not 6 weeks after aortic constriction. The maximal oxygen consumption rates of mitochondria, when determined in the skinned cardiac fibers, also decreased 2 (47%) and 4 weeks (36%), but reversed 6 weeks after pressure-overload. However, the myocardial ATP, a utilizing form of high-energy phosphate, of pressure-overloaded rat myocardium remained normal at all times after cardiac hypertrophy. This suggests that alterations in hemodynamic variables of in vivo pressure-overloaded rats may not be attributable to a reduction in the myocardial energy production. In the perfused hearts isolated from pressure-overloaded rats, tissue ATP levels were similar to those of sham-operated rats, although the tissue creatine phosphate tended to be reduced in the pressure-overloaded animals at all stages of cardiac hypertrophy examined. Only a marginal decrease in the tissue high-energy phosphate (13%) was observed 4 weeks after the operation relative to that of sham-operated rats. In contrast, the developed tension of the perfused pressure-overloaded rat hearts was consistently lower (27 to 36%) than that of the sham-operated rat hearts. The results suggest that the high-energy phosphate levels of pressure-overloaded rat myocardium in vitro are unlikely to account for the observed decline in cardiac contractile function. The reduction of myocardial high-energy phosphates of pressure overloaded rats may be due to an adaptative change rather than a causal events.

Adenosine Triphosphate↗
PubMed1993

Expression of a lymphocyte adhesion molecule (CD44) in malignant lymphomas: relevance to primary site, histological subtype and clinical stage.

Lymphocyte adhesion molecules defined by anti-CD44 antibody (Hermes-3) may be involved in lymphocyte binding to high endothelial venules at sites where lymphocytes exist the blood. CD44 expression was immunohistochemically examined in 167 well characterized cases of malignant lymphomas (MLs). None of 12 nodal follicular lymphomas (FLs) were CD44+, whereas 3 of 4 extranodal ones showed distinct CD44 expression. In contrast to nodal FLs, 28 of the 38 (74%) nodal diffuse B-cell lymphomas were CD44+ (p < 0.0001). T-cell lymphomas showed a significantly higher expression of CD44 antigen than diffuse B-cell lymphomas in the nodal cases (p < 0.04), but not in the extranodal ones. In nodal diffuse lymphomas, 3 of 5 stage I lymphomas (60%) were CD44+ in contrast to 53 of 63 stage II-IV lymphomas (84%), but the difference was not statistically significant. Of 14 Hodgkin's diseases, 9 cases were CD44+ with no significant correlation with clinical stage. The data of flow cytometric analysis confirmed the results of immunohistochemical analysis. In conclusion, CD44 expression is relevant to primary sites of distinctive MLs originating in the mucosal regions (MALToma) and some histological subtypes, but the relation with clinical stage was not defined. Some other adhesion molecules or different mechanisms must also be taken into account concerning the genesis and the expansion of MLs.

Humans↗
PubMed1993

[Longterm clinical results of transurethral incision of prostate and bladder neck for benign prostatic hypertrophy].

Early and longterm results of transurethral incision of the prostate and bladder neck (TIPBn) were compared with those of transurethral resection of the prostate (TURP) in treatment of 36 patients with outflow obstruction caused by small benign prostatic hypertrophy. Seventeen patients underwent TIPBn and 19 TURP. Parameters on uroflowmetry (maximum flow rate, average flow rate, voiding time and residual rate) were significantly improved postoperatively in both groups. There was no significant difference in the improvement on uroflowmetry both at early (3 months) and longterm (TIPBn: 12-48, mean 20.1 months, TURP: 12-48, mean 22.2 months) postoperative periods, between the two groups. Subjective symptom of voiding difficulty was remarkably improved in all patients of both groups during early postoperative period. However, at longer follow-up, subjective improvement was preserved in 88.2% in the TIPBn group and 73.7% in the TURP group. A re-operation was needed in 4 cases (21.5%) in the TURP group because of recurrence of obstructive symptom due to postoperative bladder neck contracture, while a second operation has not been performed in the TIPBn group. We conclude that TIPBn can be the preferred surgical treatment of outflow obstruction caused by small benign prostatic hypertrophy.

Aged↗
PubMed1993

[Response of the human neurogenic bladder induced by intramural nerve stimulation].

The detrusor contraction induced by intramural nerve stimulation in human neurogenic bladders was investigated in comparison with control bladders. All the cases with the neurogenic bladder underwent ileocystoplasty in order to resolve intractable incontinence and/or vesicoureteral reflux due to low bladder compliance or severe detrusor uninhibited contraction. 1. The dose-response curve and ED50 value for KCl were not different between neurogenic and control bladders. 2. The response of neurogenic bladders induced by intramural stimulation was significantly stronger than that of control bladders. 3. After application of 10(-6) M atropine remaining contraction of neurogenic bladders was significantly greater than that of control bladders, i.e. 28.4% and 3.7% respectively. However, 10(-6) M tetrodotoxin almost completely inhibited the detrusor contraction in both groups. 4. The subthreshold KCl (5 mM or 10 mM) enhanced the detrusor contractility significantly in control bladders compared to neurogenic bladders. 5. After bathing medium was replaced into Ca-free Krebs' solution, the contractile response was decreased. The contraction of neurogenic bladders in Ca-free solution persisted longer than that of controls. In conclusion, though there was no intrinsic difference in detrusor contractility, contractile response to electrical field stimulation, atropine resistance, enhancement of response by potassium, and contractility in Ca-free solution were significantly different between neurogenic and control bladders.

Adolescent↗
PubMed1993

[Antibiotic prophylaxis for transurethral resection of the prostate--comparison of oral administration therapy with intravenous administration therapy].

To compare the prophylactic effect of oral and intravenous antibiotics against postoperative fever and urinary tract infection (UTI) after transurethral resection of the prostate (TUR-P), we conducted a multi-center prospective randomized study. The incidence of pyrexia over 38 degrees C was defined as the primary endpoint. One hundred and fifty patients with sterile urine before TUR-P were entered into this study. The patients were allocated randomly into the two arms; arm A cefotiam 4 g a day for 7 days, arm B tosufloxacin 300 mg a day for 7 days, based on the stratification into the 4 groups determined with/without preoperative indwelling catheters and with/without the history of preoperative UTI. Of these patients, 143 were eligible. We divided 124 patients without preoperative UTI and without indwelling catheters as the "low risk group", and the other 19 patients with preoperative UTI and/or with indwelling catheters as the "high risk group". In the low risk group, 9 patients out of 63 (14.3%) in arm A and 6 out of 61 (9.8%) in arm B had pyrexia during 7 postoperative days. The incidence of fever in arm B was 4.4% less than that in arm A and the 95% confidence limit was from -7% to 16%. In the high risk group, 4 out of 11 (36.4%) patients in arm A and none of 8 in arm B had fever but the difference was not significant. The incidence of post operative UTI in the low risk group on the 4 to 5, 9 to 12, 23 to 26 and 37 to 40 postoperative days was 8.3, 16.4, 25.0 and 23.9% in arm A and 6.7, 16.7, 29.6 and 36.7% in arm B, respectively. The prophylactic effect of oral administration of tosufloxacin is equivalent to that of the intravenous administration of cefotiam. The use of oral antibiotics is beneficial to reducing the cost of medication.

Administration, Oral↗
PubMed1993

Prostate-specific antigen levels in acute and chronic bacterial prostatitis.

Prostate-specific antigen (PSA) is now widely accepted as a useful tumor marker for the diagnosis and follow-up of prostatic cancer. An elevated level of PSA has been asserted to be highly specific for prostate cancer, although patients with large benign prostate glands and those with bacterial prostatitis may also have slightly elevated levels. We measured the serum PSA level in the patients with acute and chronic bacterial prostatitis and consecutively monitored the PSA level in 6 patients who had acute prostatitis and an elevated PSA level. The PSA level was found to be elevated during the acute phase of prostatic inflammation, and the elevated, PSA level in the patients with acute prostatitis returned to the normal level within 14 days after initiation of antimicrobial therapy in all 6 patients. In one patient with chronic prostatitis the elevated PSA level persisted after antibiotic treatment. He was found to have adenocarcinoma by transrectal ultrasonography and biopsy. A markedly elevated serum PSA level in bacterial prostatitis can cause confusion in the diagnosis of prostatic carcinoma. Therefore, PSA determination should be obtained after complete clinical resolution of inflammation to exclude prostatic malignant involvement.

Acute Disease↗
PubMed1993

[Clinical usefulness of newly developed urine protein dipstick (URINE-TP)].

We assessed the clinical usefulness of a newly developed urine protein dipstick (URINE-TP; U-TP) which can detect gamma-globulin and other proteins as well as albumin. Semiquantitative values of urine protein evaluated with U-TP were compared with those evaluated with ordinary urine protein dipsticks (BM-TEST) in 966 urine samples. The two tests showed the same semiquantitative values in 572 of 966 samples (59.2%; Group A). However, U-TP showed a more positive reaction two gradations higher in 89 samples (9.2%; Group B), and showed a more positive value with one gradation higher in 283 samples (29.3%; Group C) compared with BM-TEST. We then measured total protein, alpha 1-microglobulin (alpha 1-M), NAG and beta 2-microglobulin (beta 2-M) in urine, and serum beta 2-M, urea nitrogen (UN) and creatinine (CRE) in both Group A and Group B. In BM-TEST negative patients, urinary total protein, tubular proteins (alpha 1-M, beta 2-M) and NAG were significantly higher (p < 0.01) in Group B than in Group A. Moreover, among patients who had trace or positive results by BM-TEST, serum UN was significantly higher (p < 0.01) in Group B than in Group A. These results suggest that U-TP, a newly developed urine protein dipstick, can detect tubular proteins which cannot be detected by ordinary dipsticks. U-TP may be useful for early detection of renal tubular damage, especially when use is the combined with conventional dipsticks.

Acetylglucosaminidase↗
PubMed1993

Evidence for active transport of 3H-androgens across the epididymal epithelium in the rat.

The effect of metabolic inhibitors on transepithelial movement of 3H-androgens was investigated by in vivo perifusion and subsequent micropuncture of caput and cauda epididymal tubules. Epididymal tissue (adenosine triphosphate (ATP) concentrations were determined at 1 h after exposure of perifusion fluid with metabolic inhibitor. To determine whether or not metabolic inhibitor alters intraluminal androgen-binding protein concentration or androgen binding to interstitial proteins in the caput epididymis, 3H-dihydrotestosterone (DHT) binding to interaluminal androgen-binding protein and bound vs free androgen ratio in the interstitial fluid after 1 h perifusion with fluid containing metabolic inhibitor around caput epididymal tubules were examined. Proluminal movement of 3H-androgens and tissue ATP concentrations in the caput and cauda epididymis were significantly decreased by addition of dinitrophenol (DNP) or potassium cyanide to the perifusion fluid. Relative intraluminal androgen-binding protein protein concentration and bound vs free 3H-androgen ratio in the interstitial fluid were not altered when DNP or potassium cyanide was added to the perifusion fluid. These results demonstrate for the first time that an energy-dependent mechanism may be involved in the epididymal androgen uptake.

Animals↗
PubMed1993

Transepithelial movement of 3H-androgen in rat seminiferous and caput epididymal tubules: saturability and effect of competition with estradiol.

Proluminal movement of 3H-testosterone from peritubular space to intratubular fluids of the adult rat testis and epididymis was studied by using in vivo microperfusion and subsequent micropuncture of seminiferous tubules and caput epididymal tubules. Tubules were perifused with Minimum Essential Medium containing 3H-testosterone. To determine if androgen transport is saturable, 40, 80, 160, and 320 microCi 3H-testosterone were included in the perfusion fluid. Radioactivity of 3H-androgens in the intraluminal fluids was determined at 1 hour after perfusion. Transepithelial 3H-androgen movement in the testis was linear (r = 0.735, p < 0.001, y = 0.17 x +5.6). The movement of 3H-androgen across the epididymal epithelium was saturable (Vmax of 326.5 nM/hr and Km of 77 nM). To determine the effect of estradiol on proluminal androgen movement, estradiol at 10X the cocentration of 3H-testosterone was incorporated in the perifusion fluid. Proluminal 3H-androgen movement into the seminiferous and epididymal tubules was not affected by addition of estradiol to the perifusion fluid. These findings support our previous observations that proluminal transepithelial movement of 3H-androgens could be mediated by its binding to a specific intraluminal androgen binding protein.

Animals↗